Green fluorescent protein-like pigments optimize the internal light environment in symbiotic reef building corals

  1. Elena Bollati  Is a corresponding author
  2. Niclas H Lyndby
  3. Cecilia D'Angelo
  4. Michael Kühl
  5. Jörg Wiedenmann
  6. Daniel Wangpraseurt  Is a corresponding author
  1. University of Copenhagen, Denmark
  2. Ecole Polytechnique Fédérale de Lausanne, Switzerland
  3. University of Southampton, United Kingdom
  4. University of California, San Diego, United States

Abstract

Pigments homologous to the Green Fluorescent Protein (GFP) have been proposed to fine-tune the internal light microclimate of corals, facilitating photoacclimation of photosynthetic coral symbionts (Symbiodiniaceae) to life in different reef habitats and environmental conditions. However, direct measurements of the in vivo light conditions inside the coral tissue supporting this conclusion are lacking. Here, we quantified the intra-tissue spectral light environment of corals expressing GFP-like proteins from widely different light regimes. We focus on (1) photoconvertible red fluorescent proteins (pcRFPs), thought to enhance photosynthesis in mesophotic habitats via wavelength conversion, and (2) chromoproteins (CPs), which provide photoprotection to the symbionts in shallow water via light absorption. Optical microsensor measurements indicated that both pigment groups strongly alter the coral tissue light environment. Estimates derived from light spectra measured in pcRFP-containing corals showed that fluorescence emission can contribute to >50% of orange-red light available to the photosynthetic symbionts at mesophotic depths. We further show that upregulation of pink CPs in shallow-water corals during bleaching leads to a reduction of orange light by 10-20% compared to low-CP tissue. Thus, screening by CPs has an important role in mitigating the light-enhancing effect of coral tissue scattering during bleaching. Our results provide the first experimental quantification of the importance of GFP-like proteins in fine-tuning the light microclimate of corals during photoacclimation.

Data availability

Data used in this study is available from https://doi.org/10.5061/dryad.0gb5mkm1z

The following data sets were generated

Article and author information

Author details

  1. Elena Bollati

    Department of Biology, University of Copenhagen, Helsingør, Denmark
    For correspondence
    elena.bollati@bio.ku.dk
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-3536-4587
  2. Niclas H Lyndby

    Laboratory for Biological Geochemistry, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0533-9663
  3. Cecilia D'Angelo

    Coral Reef Laboratory, University of Southampton, Southampton, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  4. Michael Kühl

    Department of Biology, University of Copenhagen, Helsingør, Denmark
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-1792-4790
  5. Jörg Wiedenmann

    Coral Reef Laboratory, University of Southampton, Southampton, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  6. Daniel Wangpraseurt

    Department of NanoEngineering, University of California, San Diego, San Diego, United States
    For correspondence
    dwangpraseurt@eng.ucsd.edu
    Competing interests
    The authors declare that no competing interests exist.

Funding

H2020 European Research Council (702911-BioMIC-FUEL)

  • Daniel Wangpraseurt

Gordon and Betty Moore Foundation (GMB 9325)

  • Daniel Wangpraseurt

Gordon and Betty Moore Foundation (GBMF9206)

  • Michael Kühl

Natural Environment Research Council (NE/S003533/2)

  • Jörg Wiedenmann

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Kristin Tessmar-Raible, University of Vienna, Austria

Version history

  1. Received: September 1, 2021
  2. Preprint posted: October 7, 2021 (view preprint)
  3. Accepted: July 7, 2022
  4. Accepted Manuscript published: July 8, 2022 (version 1)
  5. Version of Record published: August 1, 2022 (version 2)

Copyright

© 2022, Bollati et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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  1. Elena Bollati
  2. Niclas H Lyndby
  3. Cecilia D'Angelo
  4. Michael Kühl
  5. Jörg Wiedenmann
  6. Daniel Wangpraseurt
(2022)
Green fluorescent protein-like pigments optimize the internal light environment in symbiotic reef building corals
eLife 11:e73521.
https://doi.org/10.7554/eLife.73521

Share this article

https://doi.org/10.7554/eLife.73521

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